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A228761 Primes of the concatenated form 149x149 for some number x. 1
1496149, 1497149, 1499149, 14915149, 14924149, 14925149, 14928149, 14931149, 14942149, 14945149, 14951149, 14976149, 14985149, 14991149, 149124149, 149127149, 149132149, 149135149, 149150149, 149153149, 149159149, 149162149, 149171149, 149175149, 149187149, 149192149 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Sequence is infinite. - Charles R Greathouse IV, Sep 03 2013

LINKS

K. D. Bajpai, Table of n, a(n) for n = 1..2000

FORMULA

Primes of the form parse(cat(149,x,149)).

EXAMPLE

a(1)= 1496149 is a term in the sequence as it is a prime of the form abcxabc:  abc are square digits 1,4 and 9 in order.

MAPLE

with(StringTools): KD:= proc() local a, b;  a:= 149; b:=parse(cat(a, x, a)); if isprime(b) then RETURN(b):  fi; end: seq(KD(), x=1..1000);

MATHEMATICA

With[{c={1, 4, 9}}, Select[Table[FromDigits[Join[c, IntegerDigits[n], c]], {n, 200}], PrimeQ]](* Harvey P. Dale, Jan 14 2015 *)

PROG

(PARI) for(x=1, 1e3, if(ispseudoprime(t=eval(Str(149, x, 149))), print1(t", "))) \\ Charles R Greathouse IV, Sep 03 2013

CROSSREFS

Sequence in context: A128837 A297881 A335289 * A206060 A251973 A236499

Adjacent sequences:  A228758 A228759 A228760 * A228762 A228763 A228764

KEYWORD

nonn,base,less

AUTHOR

K. D. Bajpai, Sep 03 2013

STATUS

approved

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Last modified June 14 01:29 EDT 2021. Contains 345016 sequences. (Running on oeis4.)